Auto-scraping apparatus

ABSTRACT

An auto-scraping apparatus for a work piece of a hard rail has a driving device, a linking device and a tool device. The driving device has a connecting frame, a driving motor and a cam. The driving motor is mounted in the connecting frame. The cam is mounted on a bottom of the connecting frame and has an abutting face. The linking device is connecting to the driving device and has a main frame, an upper connecting arm, a lower connecting arm, a linking arm and a rotating wheel. The main frame is connected to the driving motor. The connecting arms are pivotally connected to the main frame and the linking arm. The rotating wheel is rotatably mounted on the upper connecting arm and abuts the abutting face of the cam. The tool device is connected to the linking device and has a tool carrier and a relieving tool.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an auto-scraping apparatus for a workpiece, and more particularly to an auto-scraping apparatus that can beassembled to a Computerized Numerical Control (CNC) machine tool easilyand can rotate to scrape a surface of the work piece accurately.

2. Description of the Prior Arts

In general, a conventional hard rail for a machine tool needs to bescraped before assembly, a scraping process is used to scrape acontacting surface of the conventional hard rail to form multiplerecesses in the contacting surfaces of the conventional hard rail. Therecesses can contain lubricant to lubricate movement of a moving elementon the hard rail, since surface roughness may affect mobility of themoving element on the conventional hard rail.

There are two conventional methods to scrape a work piece: manualscraping method and semi-automatic manual scraping method. In theconventional manual scraping method, a relieving tool is used to scraperecesses into a surface of a work piece. In the semi-automatic manualscraping method, a semi-automatic scraping machine used to scraperecesses into a surface of a work piece.

However, the conventional scraping methods are operated manually toscrape recesses in the work piece, scraping quality is dependent onworker experience and is subject to human error. In addition, theconventional methods are difficult to learn and are time-consuming.Furthermore, the conventional semi-automatic scraping machine is heavyand is not easy to operate.

To overcome the shortcomings, the present invention provides anauto-scraping apparatus for a work piece to mitigate or obviate theaforementioned problems.

SUMMARY OF THE INVENTION

The main objective of the present invention is to provide anauto-scraping apparatus for a work piece of a hard rail, and moreparticularly to auto-scraping apparatus that can be assembled to a CNCmachine tool easily and can rotate to scrape a surface of the work pieceaccurately.

The auto-scraping apparatus for a work piece of a hard rail inaccordance with the present invention has a driving device, a linkingdevice and a tool device. The driving device has a connecting frame, adriving motor and a cam. The driving motor is mounted in the connectingframe. The cam is mounted on a bottom of the connecting frame and has anabutting face. The linking device is connected to the driving device andhas a main frame, an upper connecting arm, a lower connecting arm, alinking arm and a rotating wheel. The main frame is connected to thedriving motor. The connecting arms are pivotally connected to the mainframe and the linking arm. The rotating wheel is rotatably mounted onthe upper connecting arm and abuts the abutting face of the cam. Thetool device is detachably connected to the linking device and has a toolcarrier and a relieving tool.

Other objectives, advantages and novel features of the invention willbecome more apparent from the following detailed description when takenin conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of an auto-scraping apparatus in accordancewith the present invention;

FIG. 2 is an exploded perspective view of the auto-scraping apparatus in

FIG. 1;

FIGS. 3 to 5 are operational side views of the auto-scraping apparatusin

FIG. 1 scraping a work piece of a hard rail; and

FIG. 6 is a side view of the auto-scraping apparatus in FIG. 1 mountedon a CNC machine tool.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

With reference to FIGS. 1 to 3, an auto-scraping apparatus for a workpiece (40), such as a hard rail, in accordance with the presentinvention comprises a driving device (10), a linking device (20) and atool device (30).

With reference to FIG. 6, the driving device (10) may be mounted on aspindle (51) of a CNC machine tool (50) above a working table (52) andhas a connecting frame (11), a driving motor (12) and a cam (13).

The connecting frame (11) is connected to the spindle (51) of the CNCmachine tool (50) and has a top, a bottom and a connecting rod (111).The connecting rod (111) is mounted on and protrudes from the top of theconnecting frame (11) and is connected to the spindle (51) of the CNCmachine tool (50).

The driving motor (12) is securely mounted in the connecting frame (11)and has a bottom and a driving shaft (121). The driving shaft (121) isrotatably connected to the bottom of the driving motor (12), extends outof the bottom of the connecting frame (11) and has a free end.

The cam (13) may be semicircular, is securely mounted on the bottom ofthe connecting frame (11) beside the driving shaft (121) of the drivingmotor (12) and has a top side, a bottom side, a thickness, a middle, twoends and an abutting face (131). The top side of the cam (13) issecurely mounted on the bottom of the connecting frame (11). Theabutting face (131) is wavy and is formed on the bottom side of the cam(13). The thickness of the cam (13) at the middle is wider than thethickness of the cam (13) at the ends.

The linking device (20) is securely connected to the driving device (10)and has a main frame (21), an upper connecting arm (22), a lowerconnecting arm (23), a linking arm (24) and a rotating wheel (25).

The main frame (21) may be U-shaped, is securely connected to thedriving motor (12) and has a top side and a bottom side. The top side ofthe main frame (21) is securely mounted around the free end of thedriving shaft (121) of the driving motor (12).

The upper connecting arm (22) is pivotally connected to the main frame(21) near the top side and has a connecting end opposite to the mainframe (21) and a top side.

The lower connecting arm (23) is pivotally connected to the main frame(21) near the bottom side under the upper connecting arm (22) and has aconnecting end opposite to the main frame (21) and a bottom side. Thelinking arm (24) is pivotally connected to the connecting ends of theconnecting arms (22, 23) to form a four-bar-mechanism with the mainframe (21) and the connecting arms (22,23).

The rotating wheel (25) is rotatably mounted on the top side of theupper connecting arm (22) near the connecting end, abuts the abuttingface (131) of the cam (13) and has two holding mounts (251). The holdingmounts (251) are securely mounted on the top side of the upperconnecting arm (22) to hold the rotating wheel (25) on the upperconnecting arm (22).

The tool device (30) is detachably connected to the linking device (20)and has a tool carrier (31) and a relieving tool (32). The tool carrier(31) is securely mounted on the bottom side of the lower connecting arm(23) by fasteners and has a mounting surface (311) opposite to the lowerconnecting arm (23). The relieving tool (32) is securely mounted on themounting surface (311) of the tool carrier (31).

When the auto-scraping apparatus in accordance with the presentinvention is used to scrape recesses in a work piece, the driving motor(12) is electrically connected to a computer. The computer comprises ashaft controlling card and a controlling program formed by a software ofLaboratory Virtual Instrumentation Engineering Workbench (Lab-View).Then, the computer can control the rotation of the driving shaft (121)of the driving motor (12). With further reference to FIG. 6, theconnecting rod (111) of the connecting frame (11) is securely connectedto a spindle (51) of a CNC machine tool (50) and a work piece (40) issecurely mounted on a working table (52) of the CNC machine tool (50).Before scraping the work piece (40), the spindle (51) is moved downwardalong a Z axis direction by a three dimensional moving device of the CNCmachine tool (50) to correct pressure and record moving value of thethree dimension moving device. Then, location of the linking device (20)is adjusted relative to the work piece (40) by the three dimensionalmoving device of the CNC machine tool (50).

After adjusting the location of the linking device (20), the drivingmotor (12) is actuated by the computer, the linking device (20) isrotated relative to the connecting frame (11) by the driving shaft(121). With reference to FIG. 3, the rotating wheel (25) rotatesrelative to the upper connecting arm (22) when the linking device (20)is rotated with the driving shaft (121) along the abutting face (131) ofthe cam (13) between the middle and one of the ends of the cam (13).With reference to FIG. 4, when the rotating wheel (25) rotates and movesto the middle of the cam (13) that is thicker than the ends of the cam(13), the linking device (20) is pushed to move downward by the middleof the cam (13) toward the work piece (40). Consequently, the relievingtool (32) of the tool device (30) can scrape the work piece (40) to forma recess (41) on a surface of the work piece (40). With reference toFIG. 5, when the rotating wheel (25) rotates and moves to the other endof the cam (13), the linking device (20) returns back to an originalheight to move the relieving tool (32) of the tool device (30) away fromthe surface of the work piece (40).

The driving shaft (121) is rotated in a circular motion route relativeto the connecting frame (11) by the driving motor (12) and the circularmotion route can be delineated into two semicircular motion routes,respectively a front semicircular motion route and a rear semicircularmotion route. In the front semicircular motion route of the drivingshaft (121), the rotating wheel (25) moves and abuts the abutting face(131) of the cam (13) and the driving shaft (121) is rotated at a fixedrotating speed to allow the relieving tool (32) scraping the surface ofthe work piece (40). In the rear semicircular motion route of thedriving shaft (121), the rotating wheel (25) moves away from theabutting face (131) of the cam (13) and the driving shaft (121) isrotated back to the original position and the rotating speed of thedriving shaft (121) is decelerated to zero. Furthermore, during the rearsemicircular motion route of the driving shaft (121), the auto-scrapingapparatus moves relative to the work piece (40) by the three dimensionmoving device of the CNC machine tool (50) to form a new recess (41) onthe work piece (40) in a next circular motion route of the driving shaft(121). Repeating the aforementioned scraping process, multiple recesses(41) can be quickly and accurately formed in the surface of the workpiece (41) by the motion of the auto-scraping apparatus.

The whole weight of the auto-scraping apparatus in accordance with thepresent invention is only 3.5 kilogram and can be easily assembled to aCNC machine tool (50) by the connecting rod (111) connected to a spindle(51) of the CNC machine tool (50). The rotating speed of the drivingshaft (121) can be adjusted by the computer to control the scrapingmotion of the relieving tool (32) of the tool device (30) to formrecesses (41) in a surface of a work piece (40). The depth of eachrecess (41) in the surface of the work piece (40) can be adjusted to 10to 20 nano-meters.

Even though numerous characteristics and advantages of the presentinvention have been set forth in the foregoing description, togetherwith details of the structure and features of the invention, thedisclosure is illustrative only. Changes may be made in the details,especially in matters of shape, size, and arrangement of parts withinthe principles of the invention to the full extent indicated by thebroad general meaning of the terms in which the appended claims areexpressed.

1. An auto-scraping apparatus comprising: a driving device having aconnecting frame having a top; and a bottom; a driving motor securelymounted in the connecting frame and having a bottom; and a driving shaftrotatably connected to the bottom of the driving motor, extending out ofthe bottom of the connecting frame and having a free end; and a camsecurely mounted on the bottom of the connecting frame beside thedriving shaft of the driving motor and having a top side securelymounted on the bottom of the connecting frame; a bottom side; a width; amiddle; two ends; and an abutting face being wavy and formed on thebottom side of the cam; a linking device securely connected to thedriving device and having a main frame securely connected to the drivingmotor and having a top side securely mounted around the free end of thedriving shaft of the driving motor; and a bottom side; an upperconnecting arm pivotally connected to the main frame near the top sideof the main frame and having a connecting end opposite to the mainframe; and a top side; a lower connecting arm pivotally connected to themain frame near the bottom side of the main frame under the upperconnecting arm and having a connecting end opposite to the main frame;and a bottom side; a linking arm pivotally connected to the connectingends of the connecting arms to form a four-bar-mechanism with the mainframe; and a rotating wheel rotatably mounted on the top side of theupper connecting arm near the connecting end and abutting the abuttingface of the cam; and a tool device detachably connected to the linkingdevice and having a tool carrier securely mounted on the bottom side ofthe lower connecting arm; and a relieving tool securely mounted on thetool carrier.
 2. The auto-scraping apparatus as claimed in claim 1,wherein the connecting frame has a connecting rod formed on andprotruding from the top of the connecting frame to connect to a spindleof a Computerized Numerical Control machine tool.
 3. The auto-scrapingapparatus as claimed in claim 2, wherein the rotating wheel has twoholding mounts securely mounted on the top side of the upper connectingarm to hold the rotating wheel on the upper connecting arm.
 4. Theauto-scraping apparatus as claimed in claim 3, wherein the tool carrierhas a mounting surface opposite to the lower connecting arm; and therelieving tool is securely mounted on the mounting surface of the toolcarrier.
 5. The auto-scraping apparatus as claimed in claim 4, whereinthe width of the cam at the middle is wider than the widths of the camat the ends.
 6. The auto-scraping apparatus as claimed in claim 5,wherein the cam is semicircular; and the main frame is U-shaped.
 7. Theauto-scraping apparatus as claimed in claim 1, wherein the rotatingwheel has two holding mounts securely mounted on the top side of theupper connecting arm to hold the rotating wheel on the upper connectingarm.
 8. The auto-scraping apparatus as claimed in claim 1, wherein thetool carrier has a mounting surface opposite to the lower connectingarm; and the relieving tool is securely mounted on the mounting surfaceof the tool carrier.
 9. The auto-scraping apparatus as claimed in claim1, wherein the width of the cam at the middle is wider than the widthsof the cam at the ends.
 10. The auto-scraping apparatus as claimed inclaim 1, wherein the cam is semicircular; and the main frame isU-shaped.